The NHLBI Percutaneous Transluminal Coronary Angioplasty (PTCA) Registry, with the University of Pittsburgh Epidemiology Datacenter as the Data Coordinating Center (DCC) from August 1980 to August 1984 has established the short term safety and efficacy of the PTCA procedure in eligible patients with coronary heart disease. By the end of the contract period, results on late mortality, morbidity, duration of angina, relief and need for subsequent revascularization will have been collected through September, 1983 for a minimum of one year of patient follow-up. Without continued follow-up, the opportunity to evaluate the long-term results of PTCA would be lost. Funds are sought to extend follow-up observations for three more years so that 1,500 Registry patients who underwent PTCA between September 1977 and September 1982 will have a minimum of five years and an average of 6.5 years of follow-up. During this period, the Datacenter will continue to assist investigators from eighteen collaborating centers to contact every patient annually and to obtain the necessary standardized follow-up. We aim to maintain the 98% rate of follow-up which was achieved during the contract. Survival analysis methods will be used to establish rates of morbidity, mortality, and need for further revascularization. Estimation of the symptom-free time interval after PTCA will be a major focus in the analysis. We will seek to identify predictors of long-term survival, morbidity and need for further procedures. Results in clinically relevant subgroups such as those with initially successful procedures, the elderly, those with unstable angina and those with multivessel disease will be described. The long-term findngs of this study are critical for the scientific assessment of PTCA. This therapy is already widely practiced in the treatment of coronary heart disease. Indeed, the latest estimates show that over 27,000 PTCAs were performed in the U.S. during 1983, more than 2.5 times the 1982 total.